Data & Statistics guide at the University of Manchester: Understanding statistics

“Facts are stubborn things, but statistics are pliable.” ― Mark Twain

Statistics help us to understand complex situations and analyse events, but they can also be used to misrepresent and distort our picture of the world. This may be done deliberately, through the selective use of data or misleading language, but it can often be the unintentional result of flawed information gathering and interpretation, leading to unsupported conclusions or oversimplified analysis.

Most of us are not mathematicians and we can struggle to understand the context and meaning of statistics, probabilities and risks. However, there are several useful and reliable guides that can help you take a critical approach to reading statistics and avoid some of the common pitfalls and errors. 

Statistics cover methods and procedures for collecting, managing, analysing and consequently presenting quantitative data.

Statistics can be a very important asset when compiling information and supporting your work.

Think about the following questions when you are deciding if a source of statistical data would be useful for your studies.

• Authority - Who is the author? Is it a commercial document? Is it from the government?  What are the qualifications/authority of the producer of the information?
• Date - What is the date range of the data, and is it supposed to be historical or current?
• Purpose - Where has the data been published? What type of publication and who is the information for? Can you detect any bias? Are they trying to sell something or emphasise a particular outcome?
• Content - Is the data accurate and how can it be verified? Does there appear to be bias? 
• Coverage - Is the coverage complete? What is the population, or sample size, of the study? How did the researchers select the sample? Was it a random selection or a specific group? Have they chosen a selection of the data to prove their viewpoint?
• Presentation - Has the data been repackaged? For example, government data published by a private source might not be as complete as the original study. 
• Data Source - Is the data from a primary source? If the data is from a secondary source (such as the Statistical Abstract), has it been properly documented so you can find the primary source? 

• University of Brighton Statistics Guide
• University of Sheffield Guide for Statistical Information

RBA Statistics – statistics guide includes many useful links to statistical sources